Abstract The isobaric heat capacities of seven ionic liquids (ILs) based on the S-alkyl-tetrahydrothiophenium cation [CnTHT] with alkyl chain lengths of Cn = 4,5,6,7,8,9,10 and the bis[(trifluoromethyl)sulfonyl]imide, [NTf2] anion were measured in a differential scanning calorimeter in the temperature range 310−376 K. Measurements have been performed for the first time. Experimental results were extrapolated to the reference temperature of 298 K. A linear trend of the C p, m o ( l i q , 298 K ) -values for [CnTHT][NTf2] with the growing alkyl chain length was observed and compared with trends available for the other ILs with 5-membered (imidazolium and pyrrolidinium) and 6-membered (pyridinium) ring cations as [NTf2] salts. The new C p, m o ( l i q , 298 K ) -values for for [CnTHT][NTf2] were used for mutual validation of experimental and theoretical results by a group-additivity method available in the literature. The agreement observed between experimental and additive calculations, together with the reasonable chain-length dependence demonstrated for the [CnTHT][NTf2] series was considered as evidence of internal consistency of the heat capacities measured in this work.

中文翻译：

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基于四氢噻吩阳离子和NTf2阴离子的离子液体的热容量

摘要 基于烷基链长度为 Cn = 4,5,6,7,8,9,10 的 S-烷基-四氢噻吩鎓阳离子 [CnTHT] 和双 [(三氟甲基) 阳离子 [CnTHT] 的七种离子液体 (ILs) 的等压热容) 磺酰]亚胺、[NTf2] 阴离子在差示扫描量热仪中在 310-376 K 的温度范围内测量。测量是第一次进行。将实验结果外推到 298 K 的参考温度。 观察到 [CnTHT][NTf2] 的 C p, mo ( liq , 298 K ) - 值随烷基链长度增加的线性趋势，并与可得到的趋势进行比较其他具有 5 元（咪唑鎓和吡咯烷鎓）和 6 元（吡啶鎓）环阳离子的 IL 作为 [NTf2] 盐。新的 C p, mo ( liq , 298 K ) - [CnTHT][NTf2] 的值用于通过文献中可用的组可加性方法相互验证实验和理论结果。在实验和加法计算之间观察到的一致性，以及 [CnTHT][NTf2] 系列证明的合理链长依赖性被认为是这项工作中测量的热容量内部一致性的证据。